The present invention relates generally to fuel tanks for vehicles and, more particularly, to a fuel pump module for a fuel tank of a vehicle.
It is known to provide a fuel tank for a vehicle to hold fuel to be used by an engine of the vehicle. In some vehicles, the fuel tank includes a fuel pump module disposed therein with a removable cover sealed to the top of the fuel tank having an electrical connector and a fuel line outlet connector. The fuel pump module includes a fuel reservoir, an electrical fuel pump disposed in the reservoir with an inlet at a bottom thereof, and a secondary pump used to fill the reservoir to overfilling. This overfilling of the reservoir allows the generation of vapors due to the agitation of the fuel as well as the mixing of the hot fuel, being returned from an engine of the vehicle, with bulk fuel.
An example of a fuel pump module is disclosed in U.S. Pat. No. 5,218,942 to Coha et al. In this patent, the fuel pump module includes a fuel pump disposed in the reservoir, a low pressure conduit conducting hot return fuel back to the reservoir, a secondary pump disposed in the reservoir for pumping new fuel from the fuel tank into the reservoir, and a control which effects a recirculation mode of secondary pump operation when the new fuel level in the fuel tank is above a predetermined low level and a scavenge mode of secondary pump operation when the new fuel level in the reservoir is below the predetermined low level. The secondary pump includes a high-pressure jet pump having consistent flow and a float mechanism to switch the jet pump from drawing external fuel to the reservoir and vice versa. However, these jet pumps result in fuel pump modules that generate fuel vapors, which is undesired. Further, these jet pumps are relatively costly due to the components and assembly of the components.
Therefore, it is desirable to provide a new fuel pump module for a fuel tank in a vehicle. It is also desirable to provide a fuel pump module for a fuel tank in a vehicle that reduces vapor generation. It is further desirable to provide a fuel pump module for a fuel tank in a vehicle that eliminates jet pumps to fill the reservoir.
It is, therefore, one object of the present invention to provide a new fuel pump module for a fuel tank in a vehicle.
It is another object of the present invention to provide a fuel pump module for a fuel tank that has a reservoir fill and containment system.
To achieve the foregoing objects, the present invention is a fuel pump module for a fuel tank in a vehicle including a reservoir adapted to be disposed in the fuel tank and a partition disposed in the reservoir to divide the reservoir into a fuel sensing chamber and a fuel storage chamber. The fuel pump module also includes a conduit conducting return fuel from an engine of the vehicle to the fuel storage chamber of the reservoir. The fuel pump module includes a fuel pump disposed in the reservoir and having an inlet disposed in the fuel sensing chamber and an outlet disposed in the fuel storage chamber. The fuel pump module further includes a fuel usage priority valve to allow fuel from the fuel storage chamber to flow to the fuel sensing chamber to provide the inlet of the fuel pump with fuel from the fuel storage chamber.
One advantage of the present invention is that a new fuel pump module is provided for a fuel tank in a vehicle. Another advantage of the present invention is that the fuel pump module improves performance by eliminating parasitic losses to the fuel pump associated with jet pump operation and during switching function as no air is ingested during xe2x80x9cswitchxe2x80x9d period. Yet another advantage of the present invention is that the fuel pump module has no depletion of fuel pump output to run an aspirator as in a high pressure jet pump and no increase or fluctuation in return line pressures, as in return line jet pumps. Still another advantage of the present invention is that the fuel pump module, when operated in contained mode, delivers fuel in the reservoir to the fuel pump, which is cleaner than bulk fuel. A further advantage of the present invention is that the fuel pump module reduces cost because of the elimination of all jet pump components and assembly stations to install these components and allows usage of a smaller, lower cost fuel strainer for the fuel pump. Yet a further advantage of the present invention is that the fuel pump module improves quality by the elimination of press fits and high-pressure connections in the return fuel line, allowing simplified assembly and reduction in part count of the fuel pump module.
Other objects, features, and advantages of the present invention will be readily appreciated, as the same becomes better understood, after reading the subsequent description taken in conjunction with the accompanying drawings.